Introducer

ABSTRACT

An introducer is configured to distinguish an introducer provided with a sheath tube whose wall thickness is reduced, from an introducer provided with a sheath tube whose wall thickness is not reduced, and to recognize the relationship between the inner diameter and the outer diameter for the sheath tube in which the wall thickness is reduced. The introducer includes an introducer sheath and a three-way stopcock portion. The introducer further includes a first information piece on at least one of the introducer sheath and the three-way stopcock portion and has an inner diameter dimension of the sheath tube as an index. Furthermore, a second information piece having an outer diameter dimension of the sheath tube as an index is on at least one of the introducer sheath and the three-way stopcock portion.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/JP2013/058123 filed on Mar. 21, 2013, and claims priority toJapanese Application No. 2012-072409 filed on Mar. 27, 2012, the entirecontent of both of which is incorporated herein by reference.

TECHNICAL FIELD

The present invention generally relates to an introducer.

BACKGROUND DISCUSSION

In recent years, various types of treatments and diagnoses in themedical field have been performed using an elongated and hollowtubular-shaped medical instrument called a catheter. Examples of suchtreatment methods include directly administering an agent into anaffected area using the elongated configuration of the catheter,push-opening a narrowed section in the lumen in a living body using acatheter in which a balloon expanded by pressure is attached to a distalend of the catheter, scraping and opening the affected area using acatheter in which a cutter is attached to a distal portion of thecatheter, and closing arterial aneurysm, bleeding, or feeding bloodvessel sites with a filling material using the catheter. Other examplesalso include a treatment method of embedding and placing atubular-shaped stent which has a mesh-shaped side surface into the lumenin the living body using the catheter so as to maintain an open state ofthe narrow section in the lumen in the living body. Further, examplesinclude aspirating a thrombus within the blood vessels.

In general, an introducer is used in a case where the treatment,diagnosis, or the like is performed using the catheter. The introducerhas an introducer sheath including a sheath tube introduced to apuncture site; a dilator which is inserted into a lumen of the sheathtube; and a three-way stopcock portion which is provided so as to becommunicated with the lumen of the sheath tube. An example is disclosedin Japanese Utility Model No. 6-48684. The sheath tube is introduced toa puncture site which is formed on an arm or a leg and a catheter or thelike is percutaneously inserted into a lesion site such as the bloodvessel through the lumen of the sheath tube.

In general, the introducer is color-coded based on a color code. Thecolor code shows a maximum diameter of a device (medical instrument suchas a catheter) that can be inserted into the lumen of the sheath tube inthe introducer sheath using colors.

SUMMARY

Consideration has been given to reducing the wall thickness of a sheathtube to more easily introduce the sheath tube to a puncture site bymaking the outer diameter of the sheath tube small and to make a devicewith a large outer diameter to be able to be inserted by making theinner diameter of the sheath tube large.

Regarding an introducer provided with the sheath tube of which the wallthickness is reduced, in a case where a color code which is the same asthat of a previous sheath tube is used, there is a problem in that it isimpossible to easily recognize the difference with an introducerprovided with the previous sheath tube in which the wall thickness isnot reduced. Such a problem also arises even in both cases before andafter setting the introducer sheath and the dilator.

In addition, with respect to the sheath tube in which the wall thicknessis reduced, there is a problem in that it is impossible to recognize therelationship between the inner diameter and the outer diameter. For thisreason, it is impossible to recognize whether or not the introducer isan introducer provided with a sheath tube in which the outer diameter isreduced while maintaining the maximum diameter of the insertable medicalinstrument as it is in the previous sheath tube, or an introducerprovided with a sheath tube in which the maximum diameter of theinsertable medical instrument is made large while maintaining the outerdiameter dimension as it is in the previous sheath tube.

The introducer disclosed here makes it possible to rather easilydistinguish the introducer provided with the sheath tube in which thewall thickness is reduced, from the introducer provided with theprevious sheath tube in which the wall thickness is not reduced, andmakes it possible to relatively easily recognize the relationshipbetween the inner diameter and the outer diameter regarding the sheathtube in which the wall thickness is reduced.

An introducer includes an introducer sheath having an elongated hollowsheath tube and a sheath hub which is provided at a proximal side of thesheath tube and provided with an insertion port through which a dilatoris inserted, a three-way stopcock portion having a connection tube withone end connected to the sheath hub, and a three-way stopcock main bodyconnected to the other end of the connection tube.

A first information piece which is shown on at least one of theintroducer sheath and the three-way stopcock portion and has an innerdiameter dimension of the sheath tube as an index, and a secondinformation piece which is shown on at least one of the introducersheath and the three-way stopcock portion and has an outer diameterdimension of the sheath tube as an index.

The first information piece or the second information piece shown on thethree-way stopcock portion is shown on at least one of the connectiontube and the three-way stopcock main body, and the first informationpiece or the second information piece shown on the introducer sheath isshown on at least one of the sheath tube and the sheath hub.

The first information piece is shown at a position closer to theinsertion port of the sheath hub than the second information piece.

The sheath hub includes a sheath support body which is provided at aproximal side of the sheath tube; a housing which is provided at aproximal side of the sheath support body; a cap which is attached to thehousing and at which the insertion port is formed; and a tab portion inwhich a through hole is formed in order to fix the introducer sheath.The first information piece is shown on at least one of the sheathsupport body, the housing, the cap, and the tab portion in the sheathhub, and the second information piece is shown on at least one of thesheath support body, the housing, the cap, and the tab portion in thesheath hub.

The sheath tube to be applied includes (a) a first sheath tube in whichthe wall thickness is T1 and the outer diameter dimension is D1o, (b) asecond sheath tube in which the wall thickness is T1 which is the sameas that of the first sheath tube and the outer diameter dimension is D2o(D1o<D2o) which is set to be a size larger than the first sheath tube,and (c) a third sheath tube in which the wall thickness is T2 (T2<T1)which is thinner than the first and the second sheath tubes, the outerdiameter dimension is D3o (D1o<D3o<D2o) which is larger than the outerdiameter dimension D1o of the first sheath tube and smaller than theouter diameter dimension D2o of the second sheath tube, and the innerdiameter dimension is D3i (D1i<D3i D2i) which is larger than the innerdiameter dimension D1i of the first sheath tube and not larger than theinner diameter dimension D2i of the second sheath tube, in which thefirst information piece shown when applying the third sheath tube is thesame as the first information piece shown when applying the secondsheath tube, and in which the second information piece shown whenapplying the third sheath tube is the same as the second informationpiece shown when applying the first sheath tube.

The sheath tube to be applied includes (a) a first sheath tube in whichthe wall thickness is t1 and the outer diameter dimension is d1o, (b) asecond sheath tube in which the wall thickness is t1 which is the sameas that of the first sheath tube and the outer diameter dimension is d2o(d1o<d2o) which is set to be a size larger than the first sheath tube,and (c) a third sheath tube of which the wall thickness is t2 (t2<t1)which is thinner than the first and the second sheath tubes, the outerdiameter dimension is d3o (d3o<d1o<d2o) which is smaller than the outerdiameter dimension d1o of the first sheath tube, and the inner diameterdimension is d3i (d1i<d3i d2i) which is larger than the inner diameterdimension d1i of the first sheath tube and not larger than the innerdiameter dimension d2i of the second sheath tube, in which the firstinformation piece shown when applying the third sheath tube is the sameas the first information piece shown when applying the second sheathtube, and in which the second information piece shown when applying thethird sheath tube is the same as the second information piece shown whenapplying the first sheath tube.

The first information piece is configured of at least one of a color ora figure, and the second information piece is configured of at least oneof a color or a figure.

The introducer disclosed here includes the first information piecehaving the inner diameter dimension of the sheath tube as an index andthe second information piece having the outer diameter dimension of thesheath tube as an index, on the introducer sheath or the three-waystopcock portion. Therefore, it is possible to easily recognize thedifference between the introducer provided with the sheath tube in whichthe wall thickness is reduced and the introducer provided with theprevious sheath tube in which the wall thickness is not reduced. Forexample, in a case where the first information piece is a Fr size of thesheath tube having an inner diameter dimension of the sheath tube as anindex and the second information piece is a Fr size of the sheath tubehaving an outer diameter dimension of the sheath tube as an index, thefirst information piece and the second information piece are the same aseach other in a case of the previous sheath tube of which the wallthickness is not reduced. On the other hand, in a case of the sheathtube in which the wall thickness is reduced, it is possible to reducethe size of the outer diameter dimension by, for example, reducing oneFr size at the same inner diameter dimension, and therefore, the firstinformation piece and the second information piece are different fromeach other. In other words, when the first information piece and thesecond information piece are the same as each other, a user can easilyidentify that the used introducer is the introducer provided with theprevious sheath tube in which the wall thickness is not reduced.Meanwhile, when the first information piece and the second informationpiece are different from each other, a user can easily identify that theused introducer is the introducer provided with the sheath tube in whichthe wall thickness is reduced.

Furthermore, since the introducer is provided with the first informationpiece having the inner diameter dimension of the sheath tube as an indexand the second information piece having the outer diameter dimension ofthe sheath tube as an index, the relationship between the inner diameterand the outer diameter becomes clear with respect to the sheath tube inwhich the wall thickness is reduced.

In this manner, a user can recognize whether or not the sheath tube isthe sheath tube in which the wall thickness is reduced and can recognizethe relationship between the inner diameter and the outer diameter withrespect to the sheath tube in which the wall thickness is reduced whilepreparing or using the introducer. Accordingly, it is possible tosmoothly and promptly proceed with the preparation work of a device tobe inserted next and to prevent misidentification of the device size.

It is possible to employ a mode showing both the first information pieceand the second information piece on the introducer. Moreover, individualmembers which are included in the introducer sheath can be set to showthe first information piece or the second information piece andindividual members which are included in the three-way stopcock portioncan be set to show the first information piece and/or the secondinformation piece.

The inner diameter of the sheath tube is shown at a position close tothe insertion port of the sheath hub. Therefore, it is easy to recognizethe maximum size of a device that can be inserted into the insertionport.

It is possible to show the first information piece and the secondinformation piece on individual members which are included in the sheathhub.

The third sheath tube is the sheath tube in which the wall thickness isreduced compared to the first and the second sheath tubes. The outerdiameter dimension thereof is the same as that of the first sheath tubeand the inner diameter dimension is the same as that of the secondsheath tube. Therefore, it is possible to insert a device having a sizelarger while reducing the size of the outer diameter.

The third sheath tube is the sheath tube in which the wall thickness isreduced compared to the first and the second sheath tubes, and the outerdiameter dimension thereof is smaller than the first and the secondsheath tubes. Therefore, it is possible to insert a device by reducingthe size of the outer diameter. In addition, when the inner diameterdimension is a size between the inner diameter dimensions of the firstand the second sheath tubes, a device having a size larger can beinserted.

It is also possible to simply show the first and the second informationpieces using a color and/or a figure.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view showing a schematic configuration of an introducerin a state where an introducer sheath and a dilator are set.

FIG. 2 is a plan view showing a schematic configuration of an introducerin a state where an introducer sheath and a dilator are disassembled.

FIG. 3 is a cross-sectional view showing a main section of anintroducer.

FIG. 4 is a view showing a state where a catheter is inserted through anintroducer sheath introduced to a puncture site.

FIGS. 5(A) and 5(D) are cross-sectional views showing sheath tubes inwhich the wall thicknesses (t=T1) are relatively thick and FIGS. 5(B)and 5(C) are cross-sectional views showing sheath tubes in which thewall thicknesses (t=T2, T3) are relatively thin.

FIGS. 6(A) to 6(C) are cross-sectional views illustrating first to thirdsheath tubes applied to an introducer. The third sheath tube is a sheathtube in which the wall thickness is more reduced compared to the firstand the second sheath tubes. The third sheath tube shows a tube in whichthe outer diameter dimension is the same as that of the first sheathtube and the inner diameter dimension is the same as that of the secondsheath tube and through which a device having a size larger can beinserted while reducing the size of the outer diameter.

FIGS. 7(A) to 7(C) are cross-sectional views illustrating first to thirdsheath tubes applied to an introducer. The third sheath tube is a sheathtube in which the wall thickness is more reduced compared to the firstand the second sheath tubes. The third sheath tube shows a tube of whichthe outer diameter dimension is smaller than those of the first andsecond sheath tubes and through which a device can be inserted whilereducing the size of the outer diameter.

DETAILED DESCRIPTION

Hereinafter, an embodiment of an introducer representing one example ofthe introducer disclosed here will be described with reference to theaccompanying drawings. Common features are identified by the samereference numerals throughout and a detailed description of previouslydescribed features will not be repeated. In some cases, dimensionalratios in the drawings are exaggerated and are different from the actualratios for the convenience of description.

FIG. 1 illustrates the configuration of an introducer 10 in a statewhere an introducer sheath 20 and a dilator 30 are set, FIG. 2 shows theintroducer 10 in a state where the introducer sheath 20 and the dilator30 are disassembled, FIG. 3 is a cross-sectional view showing a mainsection of the introducer 10, and FIG. 4 illustrates a catheter 70inserted through the introducer sheath 20 introduced to a puncture site.

The introducer 10 is a device that ensures an access route into a lumenin a living body. In the description below, the hand operation unit sideof the device from which the device is operated will be referred to as a“proximal side” or “proximal end”, and the side through which the deviceis inserted into the lumen in the living body will be referred to as a“distal side” or “distal end”.

To outline the introducer 10 with reference to FIGS. 1 to 3, theintroducer 10 includes the introducer sheath 20, the dilator 30, and athree-way stopcock portion 40. The introducer sheath 20 includes anelongated hollow sheath tube 21 and a sheath hub 22 which is provided atthe proximal side of the sheath tube 21 and provided with an insertionport 25 a through which the dilator 30 is inserted. The dilator 30includes a dilator tube 31 which is inserted into (positioned in) thesheath tube 21 and a dilator hub 32 which is provided at the proximalside of the dilator tube 31 and is connectable to a sheath hub 22. Thethree-way stopcock portion 40 includes a connection tube 41 possessingone end connected to the sheath hub 22 and a three-way stopcock mainbody 42 which is connected to the other end of the connection tube 41.Referring to FIG. 4, the dilator 30 is removed after the introducersheath 20 is introduced to a puncture site, and a device such as thecatheter 70 is percutaneously inserted into a lesion site such as theblood vessels or the like through a lumen of the introducer sheath 20.Compared to trans femoral intervention (TFI) in which the introducersheath 20 is introduced from a foot, trans radial intervention (TRI) inwhich the introducer sheath 20 is introduced from the arm has advantagessuch as facilitated hemostasis, shortened rest time, fewer bleedingcomplications, and the like for both patients and hospitals.Hereinafter, the introducer 10 will be described in detail.

The introducer sheath 20 remains in the lumen in the living body. Adevice such as the catheter 70, a guide wire, or an embolus material isinserted into the introducer sheath to be introduced into the lumen inthe living body.

The sheath tube 21 is percutaneously introduced into the lumen in theliving body. The sheath tube 21 possesses an elongated tubular shape andthe proximal side of the sheath tube 21 is connected to the distal sideof the sheath hub 22. The sheath tube 21 includes a distal portion 21 awith a tapering outer diameter and a main body portion 21 b with aconstant outer diameter.

Examples of the material constituting the sheath tube 21 is notparticularly limited, but it is possible to use a polymer material suchas polyolefin (for example, polyethylene, polypropylene, polybutene, anethylene-propylene copolymer, an ethylene-vinyl acetate copolymer, anionomer, and a mixture of at least two thereof), a polyolefin elastomer,a cross-linked body of polyolefin, polyvinyl chloride, polyamide, apolyamide elastomer, polyester, a polyester elastomer, polyurethane, apolyurethane elastomer, fluorine resin, polycarbonate, polystyrene,polyacetal, polyimide, polyetherimide, and aromatic polyether ketone,and a mixture thereof. An ethylene tetrafluoroethylene copolymer (ETFE)can be used suitably.

As shown in FIG. 3, the sheath hub 22 includes a sheath support body 23which is provided at the proximal side of the sheath tube 21; a housing24 which is provided at the proximal side of the sheath support body 23;a cap 25 which is attached to the housing 24 and at which the insertionport 25 a is formed; and a tab portion 26 in which a through hole 26 ais formed in order to positionally fix the introducer sheath 20.

The diameter of the distal portion of the sheath support body 23 isreduced to have a curved-surface shape in order to prevent kinking ofthe sheath tube 21. It is preferable that the quality of the material ofthe sheath support body 23 be flexible resin in order to prevent thekinking of the sheath tube 21, and a thermoplastic elastomer such asSEBS can be used.

The distal side of the housing 24 is connected to the proximal side ofthe sheath support body 23 and the proximal side of the housing 24 isextended over the sheath support body 23. A side port 27 thatcommunicates with the lumen of the sheath tube 21 is formed on the sideof the housing 24.

The material constituting the housing 24 is not particularly limited,but a hard material such as hard resin is suitable. Examples of the hardresins include polyolefin such as polyethylene and polypropylene,polyamide, polycarbonate, and polystyrene.

A hemostasis valve 28 is attached to the proximal side of the housing24. The hemostasis valve 28 has a substantially elliptical membraneshape (disk-shape). The material constituting the hemostasis valve 28 isnot particularly limited, but examples of the material include siliconerubber, latex rubber, butyl rubber, and isoprene rubber which areelastic members.

The cap 25 fixes the hemostasis valve 28 such that an outer peripheralpart of the hemostasis valve 28 is interposed between the housing 24 andthe cap 25 as shown in FIG. 3. The material constituting the cap 25 isnot particularly limited, but the material which is the same as thatconstituting the housing 24 can be applied.

The tab portion 26 is integrally provided at the proximal side of thesheath support body 23 in the embodiment shown in the drawing. That is,in this embodiment representing an example of the introducer, the tabportion 26 and the sheath support body 23 are integrally formed in onepiece as a unit. The through hole 26 a formed in the tab portion 26 anda fixing groove 23 a formed on the sheath support body 23 areappropriately used to fix the introducer sheath 20 to the puncture site.

The tab portion 26 may be a separated body from the sheath support body23. Furthermore, the tab portion 26 may be rotatably provided around theaxis of the sheath tube 21 in order to easily adjust the position of thetab portion 26 during fixing work.

The dilator 30 is used to prevent the sheath tube 21 from being kinkedand to expand the diameter of a perforation on the skin when theintroducer sheath 20 is inserted into the blood vessel.

The dilator tube 31 is inserted into the sheath tube 21. As shown inFIG. 1, the dilator tube is configured so that the distal portion of thedilator tube 31 is able to protrude from (extend distally beyond) thedistal end of the sheath tube 21.

Examples of materials constituting the dilator tube 31 include a polymermaterial such as polyolefin (for example, polyethylene, polypropylene,polybutene, an ethylene-propylene copolymer, an ethylene-vinyl acetatecopolymer, an ionomer, and a mixture of at least two thereof), apolyolefin elastomer, a cross-linked body of polyolefin, polyvinylchloride, polyamide, a polyamide elastomer, polyester, a polyesterelastomer, polyurethane, a polyurethane elastomer, fluorine resin,polycarbonate, polystyrene, polyacetal, polyimide, polyetherimide, andaromatic polyether ketone, and a mixture thereof.

The dilator hub 32 includes a locking claw 33 that extends toward thedistal side. The locking claw (distal part of the locking claw) 33includes a projection that fits into an annular groove 29 which isprovided at the proximal side of the sheath hub 22. The dilator hub 32is detachably held at the sheath hub 22 using the locking claw 33 of thedilator hub 32 and the annular groove 29 of the sheath hub 22.

The material constituting the dilator hub 32 is not particularlylimited, but a hard material such as hard resin is suitable. Examples ofthe hard resin include polyolefin such as polyethylene andpolypropylene, polyamide, polycarbonate, and polystyrene.

An end of the connection tube 41 of the three-way stopcock portion 40 isliquid tightly connected to the side port 27 which is provided in thesheath hub 22. The connection tube 41 is a tube made of polybutadieneand has flexibility, for example. The three-way stopcock main body 42 ismounted on the other end of the connection tube 41. A liquid such asphysiological saline is injected into the introducer sheath 20 throughthe connection tube 41 from a port of the three-way stopcock main body42.

FIGS. 5(A) and 5(D) are cross-sectional views showing sheath tubes 100and 103 possessing wall thicknesses (t=T1) that are relatively thick andFIGS. 5(B) and 5(C) are cross-sectional views showing sheath tubes 101and 102 possessing wall thicknesses (t=T2, T3) that are relatively thin.

As shown in FIGS. 5(A) and 5(B), the size of the outer diameterdimension φ3 can be reduced by for example, one French size (Fr size)(φ2>φ3) at the same inner diameter dimension φ1 by reducing the wallthickness (t=T2, T1>T2) of the sheath tube 101. Here, the French size(Fr size) of the sheath tube indicates a maximum diameter of a device(medical instrument such as catheter 70) that can be inserted into thelumen of the sheath tube. In addition, as shown in FIGS. 5(A) and 5(C),the inner diameter dimension φ4 can be increased (φ4>φ1) at the sameouter diameter dimension φ2 by reducing the wall thickness (t=T3, T1>T3)of the sheath tube 102. Therefore, the inner diameter dimension φ4allows insertion of a device possessing an even larger outer diameter.On the other hand, as shown in FIGS. 5(A) and 5(D), the size of theinner diameter dimension φ5 is also reduced (φ1>φ5) even when the sizeof the outer diameter dimension φ3 is reduced by downing one Fr size(φ2>φ3) with the wall thickness (t=T1) of the sheath tube 103 beingmaintained. As a result, only a device possessing a relatively smallouter diameter dimension can be inserted.

The range of applications is extended as follows by reducing the wallthickness of the sheath tube 21. Because the outer diameter of theintroducer sheath (7Fr size introducer sheath) into which a medicaldevice having 7Fr (7Fr outer diameter) is inserted was larger than theblood vessel diameter (approximately 2.9±0.6 mm) of radial artery, it isimpossible to perform TRI procedure using the device such as thecatheter 70 having 7Fr. Herein, the outer diameter dimension of theintroducer sheath can be reduced in size by one Fr (6Fr size) at thesame inner diameter dimension by reducing the wall thickness of theintroducer sheath 20. In this manner, it is possible to perform TRIprocedure using the device having 7Fr. The device (medical device) withan outer diameter of 7Fr can be inserted into the introducer sheath withan outer diameter of 6Fr size. In the present specification, such devicesize-sheath size combination is referred to as “7 in 6”. That is, theintroducer sheath expressed as “7 in 6” means the inner diameter of theintroducer sheath is sized to receive a device (medical device) havingan outer diameter of 7Fr, and the outer diameter of the introducersheath is equivalent to an outer diameter of a known introducer sheathcorresponding to 6 Fr size. Thinning the wall thickness of a known 7Frintroducer sheath makes possible the above-described “7 in 6” introducersheath. A medical device possessing 7Fr outer diameter can be insertedinto an introducer sheath expressed as “7 in 6”.

The device size-sheath size combination is not limited to the “7 in 6”and can be applied to all sizes. For example, all outer diameterdimensions can be reduced by one Fr size as “11 in 10”, “10 in 9”, “9 in8”, “8 in 7”, “7 in 6”, “6 in 5”, “5 in 4”, “4 in 3”, and “3 in 2”.

Furthermore, as the sheath outer diameter dimension is reduced by one Frsize, an insertion mark (incision) of the human body becomes smaller andthe hemostasis time is shortened. Accordingly, the hospital stay time isshortened and a physical burden on a patient and an economic burden onthe hospital become lighter.

As described above, the size of the outer diameter dimension can bereduced by one Fr size at the same inner diameter dimension by reducingthe wall thickness of the sheath tube 21. However, in regards to theintroducer 10 provided with the sheath tube 21 in which the wallthickness is reduced, in a case where the color code which is the sameas that of the previous sheath tube is used, it is impossible to easilyrecognize the difference with an introducer 10 provided with theprevious sheath tube in which the wall thickness is not reduced. Inaddition, in regards to the sheath tube 21 in which the wall thicknessis reduced, it is impossible to recognize the relationship between theinner diameter and the outer diameter.

The introducer 10 of the present embodiment which addresses theabove-described problem caused when the wall thickness of the sheathtube 21 is reduced.

As described above, the introducer 10 of the present embodiment has theintroducer sheath 20 and the three-way stopcock portion 40. Theintroducer sheath 20 includes the elongated hollow sheath tube 21 andthe sheath hub 22 which is provided at the proximal side of the sheathtube 21 and provided with the insertion port 25 a through which thedilator 30 is inserted. The three-way stopcock portion 40 includes aconnection tube 41 possessing one end connected to the sheath hub 22 anda three-way stopcock main body 42 which is connected to the other end ofthe connection tube 41. The introducer 10 further includes a firstinformation piece 51 which is shown on at least one of the introducersheath 20 and the three-way stopcock portion 40 and has an innerdiameter dimension of the sheath tube 21 as an index (information (e.g.,color) expressing the inner diameter dimension of the sheath tube 21),and a second information piece 52 which is shown on at least one of theintroducer sheath 20 and the three-way stopcock portion 40 and has anouter diameter dimension of the sheath tube 21 as an index (information(e.g., color) expressing the outer diameter dimension of the sheath tube21).

In the present embodiment, the first information piece 51 is configuredof a color and the second information piece 52 is also configured of acolor.

The portions of the introducer 10 to show the first information piece 51and the second information piece 52 can be appropriately modified. Inthe present embodiment, the first information piece 51 or the secondinformation piece 52 is shown on members (sheath tube 21 and sheath hub22) included in the introducer sheath 20 and the first information piece51 or the second information piece 52 is shown on members (connectiontube 41 and three-way stopcock main body 42) included in the three-waystopcock portion 40. Possible combinations of information and locationare listed in the following Table 1.

TABLE 1 First information piece 51 Second information piece 52 (usinginner diameter (using outer diameter Com- dimension of sheath dimensionof sheath bination tube 21 as index) tube 21 as index) 1 Introducersheath 20 Three-way stopcock portion 40 2 Three-way stopcock portion 40Introducer sheath 20 3 Three-way stopcock portion 40 Three-way stopcockportion 40 4 Introducer sheath 20 Introducer sheath 20

As described above, the Fr size of the sheath tube 21 shows the maximumdiameter of the device that can be inserted into the lumen of the sheathtube 21. For example, there is a case where the first information piece51 is a Fr size of the sheath tube 21 having an inner diameter dimensionof the sheath tube 21 as an index and the second information piece 52 isa Fr size of the sheath tube 21 having an outer diameter dimension ofthe sheath tube 21 as an index. In this case, the first informationpiece 51 and the second information piece 52 are the same as each otherin a case of the previous sheath tube in which the wall thickness is notreduced. On the other hand, in a case of the sheath tube 21 in which thewall thickness is reduced, it is possible to reduce the size of theouter diameter dimension by, for example, reducing one Fr size at thesame inner diameter dimension, and therefore, the first informationpiece 51 and the second information piece 52 are different from eachother. In other words, when the first information piece 51 and thesecond information piece 52 are the same as each other, a user caneasily identify that the used introducer is the introducer 10 providedwith the previous sheath tube in which the wall thickness is notreduced. On the other hand, when the first information piece 51 and thesecond information piece 52 are different from each other, a user caneasily identify that the used introducer is the introducer 10 providedwith the sheath tube 21 in which the wall thickness is reduced.

In this manner, since the introducer 10 is provided with the firstinformation piece 51 having the inner diameter dimension of the sheathtube 21 as an index and the second information piece 52 having the outerdiameter dimension of the sheath tube 21 as an index, it is possible toeasily recognize the difference between the introducer 10 provided withthe sheath tube 21 in which the wall thickness is reduced and theintroducer 10 provided with the previous sheath tube in which the wallthickness is not reduced.

Furthermore, since the introducer 10 is provided with the firstinformation piece 51 having the inner diameter dimension of the sheathtube 21 as an index and the second information piece 52 having the outerdiameter dimension of the sheath tube 21 as an index, the relationshipbetween the inner diameter and the outer diameter becomes clear withrespect to the sheath tube 21 in which the wall thickness is reduced.

In this manner, a user such as a doctor or a nurse can recognize whetheror not the sheath tube is the sheath tube 21 in which the wall thicknessis reduced and can recognize the relationship between the inner diameterand the outer diameter with respect to the sheath tube 21 in which thewall thickness is reduced while preparing or using the introducer 10.Accordingly, it is possible to smoothly and promptly proceed with thepreparation work of a device to be inserted next and to preventmisidentification of the device size.

It is possible to select portions of the introducer 10 to show the firstinformation piece 51 and the second information piece 52. Moreover,individual members (sheath tube 21 and sheath hub 22) which are includedin the introducer sheath 20 can be set to show the first informationpiece 51 or the second information piece 52 and individual members(connection tube 41 and a three-way stopcock main body 42) which areincluded in the three-way stopcock portion 40 can be set to show thefirst information piece 51 or the second information piece 52.

Here, it is preferable that the first information piece 51 be shown(located) at a position closer to the insertion port 25 a of the sheathhub 22 than the second information piece 52. Accordingly, the innerdiameter of the sheath tube 21 is shown at a position close to theinsertion port 25 a of the sheath hub 22. Therefore, it is easy torecognize the maximum size of a device that can be inserted into theinsertion port 25 a.

From this perspective, the portions showing the first information piece51 and the second information piece 52 may be selected from the first tothe third combinations in Table 1.

In the first combination in Table 1, the first information piece 51 isshown on the entirety or the proximal portion of the introducer sheath20 and the second information piece 52 is shown on the three-waystopcock portion 40. In this case, the second information piece 52 isshown near a position, which is separated from the side port 27 of thesheath hub 22 as much as possible, for example, the three-way stopcockmain body 42 or the other end (end portion at a side to which thethree-way stopcock main body 42 is connected) of the connection tube 41.

In the second combination in Table 1, the first information piece 51 isshown on the three-way stopcock portion 40 and the second informationpiece 52 is shown on the introducer sheath 20. In this case, the firstinformation piece 51 is shown near a position, which is adjacent to theside port 27 of the sheath hub 22 as much as possible, for example, anend of the connection tube 41 (end portion at a side which is connectedto the sheath hub 22). In addition, the second information piece 52 isshown at a position, such as the sheath tube 21, which is separated fromthe side port 27 of the sheath hub 22 as much as possible.

In the third combination in Table 1, the first and the secondinformation pieces 51 and 52 are shown on the three-way stopcock portion40. In this case, the first information piece 51 is shown near aposition, which is adjacent to the side port 27 of the sheath hub 22 asmuch as possible, for example, an end of the connection tube 41 (endportion at a side which is connected to the sheath hub 22). The secondinformation piece 52 is shown near a position which is separated fromthe side port 27 of the sheath hub 22 as much as possible, for example,the three-way stopcock main body 42 or the other end (end portion at aside to which the three-way stopcock main body 42 is connected) of theconnection tube 41.

When showing the first information piece 51 or the second informationpiece 52 on the connection tube 41, the first information piece 51 orthe second information piece 52 may be shown on a member which isseparately attached to the connection tube 41 as well as directlyshowing it on the connection tube 41. For example, a flat chip such as aname plate is attached to a desired position of the connection tube 41to show the first information piece 51 or the second information piece52 on the chip, or the connection tube 41 is coated with a shrinkabletube having a different color.

It is possible to employ a mode of showing the first information piece51 or the second information piece 52 on individual members included inthe sheath hub 22 as well as showing the first information piece 51 andthe second information piece 52 on the entire sheath hub 22. The modewill be described below.

The sheath hub 22 of the present embodiment includes the sheath supportbody 23 which is provided at the proximal side of the sheath tube 21,the housing 24 which is provided at the proximal side of the sheathsupport body 23, the cap 25 which is attached to the housing 24 and atwhich the insertion port 25 a is formed, and a tab portion 26 in which athrough hole 26 a is formed in order to fix the introducer sheath 20.The three-way stopcock portion 40 includes the connection tube 41 andthe three-way stopcock main body 42. Moreover, the first informationpiece 51 and the second information piece 52 can be shown on at leastone of the sheath support body 23, housing 24, cap 25, and tab portion26 in the sheath hub 22. In addition, the first information piece 51 andthe second information piece 52 can be shown on at least one of theconnection tube 41 and the three-way stopcock main body 42. Thecombinations when showing the first information piece 51 on the sheathhub 22 of the introducer sheath 20 and the second information piece 52on the three-way stopcock portion 40 are listed in the following Table2.

TABLE 2 First information piece 51 Second information piece 52 (innerdiameter dimension of (outer diameter dimension of Combination sheathtube 21) sheath tube 21) 1 Sheath support body 23 Connection tube 41 2Housing 24 Connection tube 41 3 Cap 25 Connection tube 41 4 Tab portion26 Connection tube 41 5 Sheath support body 23 Three-way stopcock mainbody 42 6 Housing 24 Three-way stopcock main body 42 7 Cap 25 Three-waystopcock main body 42 8 Tab portion 26 Three-way stopcock main body 42

As described above, in order to facilitate easy recognition of themaximum size of a device that can be inserted into the insertion port 25a of the sheath hub 22, it is preferable that the first informationpiece 51 be shown at a position closer to the proximal portion of thedilator 30 than the second information piece 52. From this perspective,as described above, the second information piece 52 may be shown near aposition, which is separated from the side port 27 of the sheath hub 22as much as possible, for example, the three-way stopcock main body 42 orthe other end (end portion at a side to which the three-way stopcockmain body 42 is connected) of the connection tube 41. The firstinformation piece 51 may be shown on an integrated part in which twomembers, the sheath support body 23 and the tab portion 26, areintegrally formed. In addition, the first information piece 51 may beshown on an integrated part in which three members, the sheath supportbody 23, the housing 24, and the tab portion 26, are integrally formed.In addition, the second information piece 52 may also be shown on anintegrated part in which two members, the connection tube 41 and thethree-way stopcock main body 42, are integrally formed.

The sheath tube 21 which is applied to the introducer 10 will bedescribed with reference to FIGS. 6(A) to 6(C). The sheath tube 21 to beapplied includes a combination of three kinds of sheath tubes such as afirst sheath tube 61 to a third sheath tube 63 to be described below.

As shown in FIG. 6(A), in the first sheath tube 61, the wall thicknessis T1, the outer diameter dimension is D1o, and the inner diameterdimension is D11. There is an example of the previous sheath tube inwhich the wall thickness is not reduced and has a 5Fr size.

As shown in FIG. 6(B), in the second sheath tube 62, the wall thicknessis T1 which is the same as that in the first sheath tube 61, the outerdiameter dimension is D2o (D1o<D2o) which is set to be a size largerthan the first sheath tube 61, and the inner diameter dimension is D2i.For example, the sheath tube is the previous sheath tube in which thewall thickness is not reduced and has a 6Fr size.

As shown in FIG. 6(C), in the third sheath tube 63, the wall thicknessis T2 (T2<T1) which is thinner than the first and the second sheathtubes 61 and 62, the outer diameter dimension is D3o (D1o<D3o<D2o) whichis larger than the outer diameter dimension D1o of the first sheath tube61 and smaller than the outer diameter dimension D2o of the secondsheath tube 62, and the inner diameter dimension is D3i (D1i<D3i D2i)which is larger than the inner diameter dimension D1i of the firstsheath tube 61 and not larger than the inner diameter dimension D2i ofthe second sheath tube 62. The third sheath tube 63 is the sheath tube21 in which the wall thickness is reduced. The outer diameter dimensionof the third sheath tube 63 is the same as that of the previous sheathtube 21 with a 5Fr size and the inner diameter dimension of the thirdsheath tube 63 is the same as that of the previous sheath tube 21 with a6Fr size, and therefore, it is possible to insert a device having 6Frtherein. According to the way of expression in the presentspecification, the structure is referred to as a sheath tube 21 with a6- in 5-Fr size. Moreover, the first information piece 51 (that is, theinformation of the inner diameter dimension) which is shown when appliedto the third sheath tube 63 (6- in 5-Fr) is the same as the firstinformation piece 51 which is shown when applied to the second sheathtube 62 (6Fr) and the second information piece 52 (that is, theinformation of the outer diameter dimension) which is shown when appliedto the third sheath tube 63 (6- in 5-Fr) is the same as the secondinformation piece 52 which is shown when applied to the first sheathtube 61 (5Fr).

Next, another embodiment of the sheath tube 21 which is applied to theintroducer 10 will be described with reference to FIGS. 7(A) to 7(C).The sheath tube 21 to be applied includes a combination of three kindsof sheath tubes such as a first sheath tube 71 to a third sheath tube 73to be described below.

As shown in FIG. 7(A), in the first sheath tube 71, the wall thicknessis t1, the outer diameter dimension is d1o, and the inner diameterdimension is d1i. There is an example of the previous sheath tube inwhich the wall thickness is not reduced and has a 5Fr size.

As shown in FIG. 7(B), in the second sheath tube 72, the wall thicknessis t1 which is the same as that in the first sheath tube 71, the outerdiameter dimension is d2o (d1o<d2o) which is set to be a size largerthan the first sheath tube 71, and the inner diameter dimension is d2i.For example, the sheath tube is the previous sheath tube of which thewall thickness is not reduced and has a 6Fr size.

As shown in FIG. 7(C), in the third sheath tube 73, the wall thicknessis t2 (t2<t1) which is thinner than the first and the second sheathtubes 71 and 72, the outer diameter dimension is d3o (d3o<d1o<d2o) whichis smaller than the outer diameter dimension d1o of the first sheathtube 71 and smaller than the outer diameter dimension d2o of the secondsheath tube 72, the inner diameter dimension is d3i (d1i<d3i d2i) whichis larger than the inner diameter dimension d1i of the first sheath tube71 and not larger than the inner diameter dimension d2i of the secondsheath tube 72. The third sheath tube 73 is the sheath tube 21 in whichthe wall thickness is reduced. The outer diameter dimension of the thirdsheath tube 73 is smaller than that of the previous sheath tube 21 witha 5Fr size and the inner diameter dimension of the third sheath rube 73is smaller than or equal to that of the previous sheath tube 21 having a6Fr, and therefore, it is possible to insert a device with a 6Fr sizetherein. According to the way of expression in the presentspecification, the structure is referred to as a sheath tube 21 with a6- in 5-Fr size. Moreover, the first information piece 51 (that is, theinformation of the inner diameter dimension) which is shown when appliedto the third sheath tube 73 (6- in 5-Fr) is made to be the same as thefirst information piece 51 which is shown when applied to the secondsheath tube 72 (6Fr) and the second information piece 52 (that is, theinformation of the outer diameter dimension) which is shown when appliedto the third sheath tube 73 (6- in 5-Fr) is the same as the secondinformation piece 52 which is shown when applied to the first sheathtube 71 (5Fr).

Specific examples of the color codes are set forth in the followingTables 3 and 4. An example in which the first information piece 51 isshown on the sheath support body 23 and the second information piece 52is shown on the three-way stopcock main body 42 is shown in Table 3. Anexample in which the first information piece 51 is shown on thethree-way stopcock main body 42 and the second information piece 52 isshown on the sheath support body 23 is shown in Table 4. Note thatcolors which are different from the exemplified color codes, that is,colors which are not shown by the French sizes of the color codes may beshown.

TABLE 3 First information piece Second information piece 51 on sheathsupport 52 on three-way stopcock Outer Inner body 23 (visualization mainbody 42 (visualization Combination of Size diameter diameter of innerdiameter) of outer diamater) colors 7 in 6 6 Fr 7 Fr 7 Fr color (orange)6 Fr color (green) Different colors 6 6 Fr 6 Fr 6 Fr color (green) 6 Frcolor (green) Same color 6 in 5 5 Fr 6 Fr 6 Fr color (green) 5 Fr color(grey) Different colors 5 5 Fr 5 Fr 5 Fr color (grey) 5 Fr color (grey)Same colors 5 in 4 4 Fr 5 Fr 5 Fr color (grey) 4 Fr color (red)Different colors 4 4 Fr 4 Fr 4 Fr color (red) 4 Fr color (red) Samecolors 4 in 3 3 Fr 4 Fr 4 Fr color (red) 3 Fr color (purple) Differentcolors

In the combination shown in Table 3, the color code which is the same asthe sheath support body 23 may be shown on the housing 24. In addition,it is unnecessary to use the same colors and colors which are not shownby the Fr size of the sheath tube 21 may be used.

TABLE 4 First information piece 51 on three-way stopcock Secondinformation piece main body 42 52 on sheath support Outer Inner(visualization of inner body 23 (visualization of Combination of Sizediameter diameter diameter) outer diameter) colors 7 in 6 6 Fr 7 Fr 7 Frcolor (orange) 6 Fr color (green) Different colors 6 6 Fr 6 Fr 6 Frcolor (green) 6 Fr color (green) Same colors 6 in 5 5 Fr 6 Fr 6 Fr color(green) 5 Fr color (grey) Different colors 5 5 Fr 5 Fr 5 Fr color (grey)5 Fr color (grey) Same colors 5 in 4 4 Fr 5 Fr 5 Fr color (grey) 4 Frcolor (red) Different colors 4 4 Fr 4 Fr 4 Fr color (red) 4 Fr color(red) Same colors 4 in 3 3 Fr 4 Fr 4 Fr color (red) 3 Fr color (purple)Different colors

In the combination shown in Table 4, the color code which is the same asthe housing 24 may be shown on the sheath support body 23. In addition,it is unnecessary to use the same colors and colors which are not shownby the Fr size of the sheath tube 21 may be used.

As is exemplified in Tables 3 and 4, in a case where the firstinformation piece 51 is a Fr size of the sheath tube 21 having an innerdiameter dimension of the sheath tube 21 as an index and the secondinformation piece 52 is a Fr size of the sheath tube 21 having an outerdiameter dimension of the sheath tube 21 as an index, the firstinformation piece 51 and the second information piece 52 are the same aseach other in a case of the previous sheath tube in which the wallthickness is not reduced. On the other hand, in a case of the sheathtube 21 in which the wall thickness is reduced, it is possible to reducethe size of the outer diameter dimension by, for example, one Fr size atthe same inner diameter dimension, and therefore, the first informationpiece 51 and the second information piece 52 are different from eachother. In other words, when the first information piece 51 and thesecond information piece 52 are the same as each other (when the samecolor is used for the sheath support body 23 and the three-way stopcockmain body 42 in the present embodiment), a user can easily identify thatthe used introducer is the introducer 10 provided with the previoussheath tube in which the wall thickness is not reduced. Meanwhile, whenthe first information piece 51 and the second information piece 52 aredifferent from each other (when different colors are used for the sheathsupport body 23 and the three-way stopcock main body 42 in the presentembodiment), a user can easily identify that the used introducer is theintroducer 10 provided with the sheath tube 21 in which the wallthickness is reduced.

In this manner, since the introducer 10 is provided with the firstinformation piece 51 having the inner diameter dimension of the sheathtube 21 as an index and the second information piece 52 having the outerdiameter dimension of the sheath tube 21 as an index, it is possible toeasily recognize the difference between the introducer 10 provided withthe sheath tube 21 whose wall thickness is reduced and the introducer 10provided with the previous sheath tube whose wall thickness is notreduced.

Furthermore, since the introducer 10 is provided with the firstinformation piece 51 having the inner diameter dimension of the sheathtube 21 as an index and the second information piece 52 having the outerdiameter dimension of the sheath tube 21 as an index, the relationshipbetween the inner diameter and the outer diameter becomes clear withrespect to the sheath tube 21 whose wall thickness is reduced.

In this manner, a user such as a doctor or a nurse can recognize whetheror not the sheath tube is the sheath tube 21 in which the wall thicknessis reduced and can recognize the relationship between the inner diameterand the outer diameter with respect to the sheath tube 21 in which thewall thickness is reduced while preparing or using the introducer 10.Accordingly, it is possible to smoothly and promptly proceed with thepreparation work of a device to be inserted next and to preventmisidentification of the device size.

The third sheath tube 63 shown in FIG. 6(C) is the sheath tube 21 inwhich the wall thickness is reduced compared to the first and the secondsheath tubes 61 and 62. The outer diameter dimension D3o of the thirdsheath tube 63 is the same as that of the first sheath tube 61 and theinner diameter dimension D3i is the same as that of the second sheathtube 62. Therefore, it is possible to insert a device having a sizelarger while reducing the size of the outer diameter. Theabove-described effect can be exhibited in regards to the introducer 10provided with such a sheath tube 21.

In addition, the third sheath tube 73 shown in FIG. 7(C) is the sheathtube 21 in which the wall thickness is reduced compared to the first andthe second sheath tubes 71 and 72, and the outer diameter dimension d3othereof is smaller than the first and the second sheath tubes 71 and 72.Therefore, it is possible to insert a device by reducing the size of theouter diameter. In addition, when the inner diameter dimension d3i is asize between the inner diameter dimensions d1i and the d2i of the firstand the second sheath tubes 71 and 72, a device having a size larger canbe inserted. The above-described effect can be exhibited in regards tothe introducer 10 provided with such a sheath tube 21.

The embodiment in which the first information piece 51 is configured ofa color and the second information piece 52 is also configured of acolor was described, but the disclosure here is not limited to such anexample. The first information piece 51 may be configured of at leastone of a color and a figure and the second information piece 52 may beconfigured of at least one of a color and a figure. Possibleconfigurations which can be employed are set forth in the followingTable 5.

TABLE 5 First information Second information piece 51 (inner piece 52(outer Com- diameter dimension of diameter dimension of bination sheathtube 21) sheath tube 21) 1 Color Color 2 Color Figure 3 Figure Color 4Figure Figure 5 Color + figure Color 6 Color + figure Figure 7 ColorColor + figure 8 Figure Color + figure 9 Color + figure Color + figure

In this manner, it is possible to simply show the first and the secondinformation pieces 51 and 52 using a color and a figure.

The first and the second information pieces 51 and 52 are not limited tothe case of being configured by a color or a figure. A character may beused in addition to a color or a figure. In addition, it is possiblethat the first and the second information pieces 51 and 52 areconfigured of a shape. For example, it is possible to show the first andthe second information pieces 51 and 52 by providing a plurality ofkinds of projection shapes on the sheath hub 22 or the like in therequired number. It is predetermined that a projection shape in whichthe cross section has a square shape indicates “5” and a projectionshape in which the cross section has a semi-circular shape indicates“1”. Then, the sheath hub 22 may be provided with “6” for the firstinformation piece 51 or the second information piece 52 in a case wherea projection shape of which the cross section has a square shape isprovided and a projection shape of which the cross section has asemi-circular shape is provided. In a case of showing the informationusing the shape, it is possible to recognize the information throughtactile sense in addition to visual sense.

The detailed description above describes an introducer. The invention isnot limited, however, to the precise embodiments and variationsdescribed. Various changes, modifications and equivalents can beeffected by one skilled in the art without departing from the spirit andscope of the invention as defined in the accompanying claims. It isexpressly intended that all such changes, modifications and equivalentswhich fall within the scope of the claims are embraced by the claims.

What is claimed is:
 1. An introducer comprising: an introducer sheath including an elongated hollow sheath tube and a sheath hub which is provided at a proximal side of the sheath tube and provided with an insertion port configured to permit a dilator to be inserted into the insertion port; a three-way stopcock portion including a connection tube having one end configured to be connected to the sheath hub, and a three-way stopcock main body which is connected to the other end of the connection tube; and a first information piece on at least one of the introducer sheath the three-way stopcock portion and which identifies the inner diameter dimension of the sheath tube; and a second information piece on at least one of the introducer sheath and the three-way stopcock portion and which identifies the outer diameter dimension of the sheath tube.
 2. The introducer according to claim 1, wherein the first information piece or the second information piece on the three-way stopcock portion is shown on at least one of the connection tube and the three-way stopcock main body, and wherein the first information piece or the second information piece on the introducer sheath is shown on at least one of the sheath tube and the sheath hub.
 3. The introducer according to claim 1, wherein the first information piece is at a position closer to the insertion port of the sheath hub than the second information piece.
 4. The introducer according to claim 1, wherein the sheath hub includes a sheath support body at a proximal side of the sheath tube; a housing at a proximal side of the sheath support body; a cap attached to the housing and at which the insertion port is formed; and a tab portion in which a through hole is formed in order to positionally fix the introducer sheath, wherein the first information piece is on at least one of the sheath support body, the housing, the cap, and the tab portion in the sheath hub, and wherein the second information piece is on at least one of the sheath support body, the housing, the cap, and the tab portion in the sheath hub.
 5. The introducer according to claim 1, wherein the first information piece is at least one of a color and a figure, and wherein the second information piece is at least one of a color and a figure.
 6. The introducer according to claim 1, wherein the first information piece is on the introducer sheath, and wherein the second information piece is on the three-way stopcock portion.
 7. The introducer according to claim 1, wherein the sheath hub includes a sheath support body at a proximal side of the sheath tube; a housing at a proximal side of the sheath support body; a cap attached to the housing and at which the insertion port is formed; and a tab portion in which a hole is formed to positionally fix the introducer sheath, wherein the first information piece is on at least one of the sheath support body, the housing, the cap, and the tab portion in the sheath hub.
 8. The introducer according to claim 7, wherein the second information piece is on at least one of the connection tube and the three-way stopcock main body.
 9. The introducer according to claim 1, wherein the sheath hub includes a sheath support body at a proximal side of the sheath tube; a housing at a proximal side of the sheath support body; a cap attached to the housing and at which the insertion port is formed; and a tab portion provided with a through hole to positionally fix the introducer sheath, and wherein the second information piece is on at least one of the sheath support body, the housing, the cap, and the tab portion in the sheath hub.
 10. The introducer according to claim 9, wherein the first information piece is on at least one of the connection tube and the three-way stopcock main body.
 11. An introducer comprising: an introducer sheath including an elongated hollow sheath tube and a sheath hub, the elongated hollow sheath tube possessing a proximal end and the sheath hub being connected to the proximal end of the sheath tube, with a portion of the elongated hollow sheath tube and a portion of the sheath hub axially overlapping each other, the sheath hub including an insertion port configured to permit insertion of a dialator into the insertion portion, the sheath tube possessing an outer diameter and an inner diameter; and a three-way stopcock portion including a connection tube, one end of which is connected to the sheath hub, and a three-way stopcock main body which is connected to the other end of the connection tube; a first information piece on the introducer sheath or the three-way stopcock portion, and a second information piece on the introducer sheath or the three-way stopcock portion, the first and second information pieces being different from one another and identifying the sheath tube of the introducer sheath as possessing a reduced wall thickness relative to another sheath tube of the introducer sheath that possesses either an inner diameter or an outer diameter the same as the inner diameter or the outer diameter, respectively, of the sheath tube of the introducer.
 12. The introducer according to claim 11, wherein the first information piece is on the introducer sheath, and wherein the second information piece is on the three-way stopcock portion.
 13. The introducer according to claim 11, wherein the sheath hub includes a sheath support body at a proximal side of the sheath tube; a housing at a proximal side of the sheath support body; a cap attached to the housing and at which the insertion port is formed; and a tab portion provided with a through hole to positionally fix the introducer sheath, wherein the first information piece is on at least one of the sheath support body, the housing, the cap, and the tab portion in the sheath hub.
 14. The introducer according to claim 13, wherein the second information piece is on at least one of the connection tube and the three-way stopcock main body.
 15. The introducer according to claim 11, wherein the sheath hub includes a sheath support body at a proximal side of the sheath tube; a housing at a proximal side of the sheath support body; a cap attached to the housing and at which the insertion port is formed; and a tab portion provided with a through hole to positionally fix the introducer sheath, and wherein the second information piece is on at least one of the sheath support body, the housing, the cap, and the tab portion in the sheath hub.
 16. The introducer according to claim 15, wherein the first information piece is on at least one of the connection tube and the three-way stopcock main body.
 17. The introducer according to claim 11, wherein the first information piece includes a color and the second information piece includes a color.
 18. The introducer according to claim 11, wherein the first information piece is at least one of a color and a figure, and the second information piece is at least one of a color and a figure. 